- 12 - Hour Work Schedule
12 - Hour Work Schedule
By: Green Bay Metro Sewerage District
In 1983, after one of our Directors returned from a trip to Canada, literature on a 12-hour shift was brought to the attention of treatment personnel at GBMSD. At that time treatment operators were working a 7-6-7 southern swing schedule. After meeting with the Director, Treatment was given permission to research possible alternative work week schedules.
After extensive research the schedule that was selected was a "12-hour Every Other Weekend Off" schedule. With this schedule the operators worked longer periods of time when they were at work but were at less often. Instead of being at work 20 days of a 28 day schedule, with the new schedule they worked 16 of 28 days. That gave them an additional 52 days/year off work and didn't cost the District any additional payroll expense.
This new schedule was approved, work rules were modified, criteria was established for monitoring and evaluating it and in May of 1985 it went into effect on a 1 year trial basis. It has been overwhelmingly accepted and is still in use today by the Operators at GBMSD.
- Bid Document Example Page
Bid Document Example Page
By: Dean Falkner
As time goes on, I've gotten stuck writing bid documents for a variety of things. I was thinking that perhaps the web-site could be a place to provide example bid documents that people could download. Each one could have a "disclaimer" that would highlight it's for reference use only and recommend refining it to meet the community's specific needs. Here are a couple of bid documents I recently did for LaCrosse, just to provide an example.
(Other members are encouraged to send in similar samples that they've used.)
- Control of Midge Flies
Control of Midge Flies
By: Control ideas assembled by Ron Altmann
Below are a few suggestions for controlling Midge flies. I can't say there is any "one" good way of controlling the pesky flies, and what works at one wastewater plant, may not for another. I'll admit some ideas don't sound very practical (such as adding defoamer) but I did include them just incase someone could find an application. Good luck.
Bacillus Thuringuensis (BT) bacteria
Christopher Helgestad provided a wealth of information on a biological agent that uses bacillus thuringiensis bacteria (BT) to disrupt the reproduction cycle. The product he used is called Mosquito Dunks manufactured by Summit Chemical out of Baltimore, MD. Chris bought a card of twenty disks for $40.00 (2003 price), from a distributor in Wausau (phone: 715-849-1043) and provided a national distributor out of Columbus, Nebraska (phone: 1-800-228-8508). I have heard of this product before and there seems to be more then one manufacturer of the bacteria. Some are floating disks and others are rectangles. To apply BT in wastewater plants, place them within small cages or tie the disks to a rope and put them in filters, clarifiers, and aeration splitter boxes. They slowly dissolve their active ingredient and dose the water.
Wastewater operators have had success with this product. Others are afraid to use it because it is a chemical agent and may cause failure of WET testing. One operator could not get his area DNR rep. to sign off on the products use. Application at Oconomowoc was suggested at 3 lbs. to each filter a month. A supplier was given by Dick Bacon at the Oconomowoc WWTP: Smith Ecological Systems in Rockford, Illinois (phone: 815-968-8079). They will help with your questions and dosage rate.
Adding a defoamer
This has worked for mosquito control and has been suggested for midge flies, but I don't know of anyone that has had success. Possibly, it could be added to a clarifier surface and with the skimmer raised it could help in control. If you give it a try please let us know if it works. The theory is that the defoamer changes the surface tension of the water so the mosquito larva cannot penetrate the surface to breathe and thus drown.
Wastewater plants have used chlorine and hosed the surface of the water with this solution. Others have thrown in HTH (I suppose a floating device could be made so the HTH would dissolve on the surface). Some have stopped the flow to a filter or clarifier while dosing for a better kill and to give time for the chlorine to dissipate.
Commercial grade 7-Dust
This product comes dry and is made into a slurry then hosed or sprayed on the ground. The midge fly must somehow be attracted to it and die. It is not permitted for use where the effluent may contact the water supply. Sorry to say that's all the information I have on the product. If you know more please send an e-mail.
Electric bug zappers
This has been successful in covered clarifiers.
Turning off outside lighting
Of course, the tiny flies are attracted to light. When conditions are bad, some plants turn off the outside lighting, especially in the early evening.
Fathead minnows and goldfish
These have been used in traveling bridge sand filters and in clarifiers. As with attracting bats and swallows, this is a natural way of controlling midge flies. The addition of chemicals can kill off natural enemies that feed on the midge larvae.
Mixing the upper level of the clarifier
Midge files have a life cycle of; 4 days larvae, 3 days worms, and 4 days adult. In the adult stage they only fly around, reproduce, and become a nuisance. When in the larvae stage, they can live in the upper levels of a clarifier where there is not much water movement. You may notice high populations of midge larva in your clarifier and after high flows or a windy day they are gone. They are being moved out of the clarifier by the water movement. If the upper layer of the clarifier stratifies, it's midge heaven. With warmer temperatures and no currents, the upper layer also promotes algae growth. This provides food and oxygen for the larvae. Breaking up that layer may help "push" them out of the clarifier (and into your sand filters). Using a water hose to break up the stratified layer may help.
Bat houses and swallows
A plant put up bat houses and had success with attracting bats to control the flying midges. Search the Internet for "Bat houses" if you need more information on building them. Brockton Wastewater plant in Massachusetts tried to import a genus of swallows. This wasn't very successful after a few years. (Guess the swallows flew the coop.) Again, this is a natural way of controlling midge flies. Chemicals can kill off natural enemies that feed on the midge larvae.
- Some Midge fly facts:
Larvae resemble worms and are bright red. That's why they are called bloodworms.
The adult midge fly beats its wing 950 time per sec. (Hummingbirds only beat their wings at 75 beats per sec.)
The adult fly is attracted to light
Midge larvae feed on algae
- Some Midge fly facts:
- Inspecting for Illegal Sewer Connections
Inspecting for Illegal Sewer Connections
By: Dean Falkner
The issue of clear water entering collection systems leads to sewer back up, whether sewers are sized properly, have roots, or are undersized. The water also takes-up plant capacity, so this is a true loss.
We have a sewer ordinance that prohibits illegal connections. We used that basis, along with a history of back-ups as a basis to inspect homes. We hired a licensed plumber to perform the inspections for all of the many ingenious devices to get clearwater into the sewers. We bid the work and pay only $22.00 (2002 price) per inspection. We provide owners the option of a free inspection. If they opt to hire someone else or have an illegal connection identified, they have a limited time to get it fixed (after all this is a health issue impacting their neighbors). We're running nearly 100% compliance for a few thousand homes inspected.
We also copied Sheboygan's concept of a home inspection program when homes are sold. We worked with realtors for 2 years to satisfy any ideas to avoid needing the program. After the above inspections, we were still finding 10% violations. Our ordinance is predicated on the ideas that not having an illegal connection is a condition of service for any new customer. We delayed implementation for 6 months and are meeting with realtors & title companies to workout details.
Both programs are generating questions and thoughts that are leading to people doing inspections & corrective work even though the ordinance isn't even in effect yet.